For instance, Ricker cited the research of Dr. Travis Hirschi, who in 1969 identified four “bonds of attachment”: attachment, commitment, involvement and belief. “Attachment is huge,” Ricker said. “By attachment, I mean bonding with a parent or adult role model who socializes us properly. Ultimately, the child develops a belief system that some types of behavior are wrong. When attachment doesn’t occur, intense anger can replace it.”

However, lack of these four bonds of attachment does not guarantee a serial murderer. “How many people do we know who come from dysfunctional families who don’t grow up to become serial or mass murderers?” Ricker asked the packed audience, “The vast majority.”

Subtle differences exist among categorization of murderers. Ricker differentiated between mass murderers, spree killers and serial murderers, defining the latter as the FBI does: at least three deaths over time punctuated by cooling-off periods.

Mass murderers tend to dominate the headlines now. For instance, “We had a mass murder (Nov. 7) in Thousand Oaks, Calif., involving an individual who went into a bar and killed 12 people,” Ricker said. “Since 2000, there have been over 2,200 people shot in mass shootings Mass murderers maximize the number of victims during one event.”

“A lot of mass murderers have hostile feelings toward the government and society,” Ricker said. Timothy McVeigh, who perpetrated the 1995 Oklahoma City bombing that killed 168 people, “was angry with the FBI for David Koresh and the Branch Davidians in Waco in April 1993,” an incident Ricker followed closely because he worked in Houston law enforcement at the time.

Ricker also focused on juvenile mass killers. With school shootings, we often think of juvenile killers. While these juvenile killers are newsworthy, Ricker notes that of “approximately 15,000 homicides committed yearly, according to the FBI’s Uniform Crime Report, only about 10 percent are committed by juveniles.”

“Psychological and social research have been done on shooters,” Ricker said. “Bullying is one reason. The Columbine killers, Eric Harris and Dylan Klebold, initially plotted to blow up the school. Harris was a psychopath who felt no empathy or remorse. Klebold suffered from depression.” Ricker even has personal experience with juvenile killers. “When I worked at Holy Cross Children’s Services, I worked w​​ith the youngest school shooter in American history,” Ricker said of the 6-year-old boy who shot and killed a female classmate in Mount Morris in 2000.

Ricker also discussed the Macdonald triad, which links cruelty to animals, obsession with fire-setting and persistent enuresis (bedwetting) to violent behaviors, particularly homicidal behavior and sexually predatory behavior. He cited numerous examples, especially among serial killers, where extensive periods of humiliation have been found in the childhoods of several adult serial killers. This was the case with Edmund Kemper, who murdered 10 people in northern California between 1964-73, including his grandparents and mother, after a childhood in which he buried a cat alive and decapitated his sisters’ dolls.

Michigan-born Aileen Wuornos, who robbed and shot seven men in Florida between 1989-90, like (Ted) Bundy, grew up thinking her grandparents were her biological parents. The grandfather was an alcoholic who physically and sexually abused her, Ricker told the audience. Ricker even has “talked to her mother, who lives in the U.P.” Aileen “had a very troubled childhood. She did well in art, but no one ever worked with her,” Ricker said, making the audience wonder if history could have been changed by someone acknowledging her talents in art.

As the conversation turned to a lively Q&A session, Ricker conversed with his audience in Mathews Conference Center West on the Dowagiac campus about the influence of pornography and violent video games, movies and music. Ricker referenced Albert Bandura’s early 1960s Bobo doll experiment demonstrating children learn aggression can be fun by watching an adult act aggressively toward the toy that springs back upright after being knocked down. However, he, like much of the audience, stopped short of suggesting direct links between media portrayal of violence and serial murder.